Spark gap oscillation generator with radiator



June 17, 1947. H. BENloFF SPRAK GAP OSCILLATION GENERATOR WITH RADIATOR Original Filed April 50, 1941 2 Sheets-Sheet 1 l l l 5, 9 9 IW lll e! IN V EN TOR.

June 17, 1947. H. BENloFF 2,422,176

SPARK GAP OSCILLATION GENERATOR WITH RADIATOR Original Filed April 30, 1941 2 Sheets-Sheet 2 Fa@ 3 v PUT il H'HHI 5` INVENTOR.

His ATTO v Y By Lz- Patented June 17, 1947 UNITED STATES PATENT oFFicE SPARK GAP OSCILLATION GENERATOR WITH RADIATOR Hugov Benioff,- Pasadena, Calif., assignor, by mesne assignments, to Submarine Signal Company, Boston, Mass., a corporation of Delaware Original applicationApril 30, 1941, Serial No. 391,153. Divided and this application December 26, 1942, Serial No. 470,299

(Cl. Z50- 17) f 4 Claims.

The present invention is a division of application Serial No. 391,153, filed April 30, 1941.

The present invention relates to short wave transmitting apparatus and particularly to spark transmission of very high frequency electromagnetic waves. 'Y

The present invention further relates to a method and apparatus for accurately controlling the time of emission of electromagnetic wave trains at ultra-high frequencies in the range approximately of 300 megacycles and producingr very short signal impulses for the purposes of directive radiation with the use of a' radiating vhorn if desired.

The present invention further is concerned with the production and radiation of increased power at these very high frequencies and tothis end employs a special type of high frequency tankoscillator in which increased power maybe developed. This oscillator preferably contains in series a main spark gap and two auxiliary spark gaps although the auxiliary Spark gaps may be eliminated in the operation of the system. The power is supplied to this series circuit through the secondary of an air core transformer the primary of which is operated by a condenser discharge tube controlled or triggered periodically by means of a control tube, preferably a thyratron'. The circuit formed by the discharging condenser, the 'tube and transformer are arranged to have sufcient resistance to provide a highly damped type of oscillation so that only the initial oscillation will operate the circuit.

Further advantages and features ofthe present invention will be understood fromthe specification below taken Vin connection with the drawings in which Fig. 1 shows a vertical. section through the apparatus; Fig. 2 shows a modified detail of an element shown in Fig. l; Fig. 3 shows a section on the line 3-3 of Fig. 4; Fig. 4 shows a top view of the detail shown in Fig. 2; Fig. 5 shows asection on the line 5-5 of'Fig. 1; and Fig. 6 shows a circuit diagram whichA may be used in connection with any of the figures.

In Fig. 1 there is provided an airtightchamber I within a casing 2 which may be made of metal or conducting material with a valve 3 at one side through which air or gas may be pumped under pressure. The top of the casing is covered by a plate 4 which hermetically sealsv the casing by means of the bolts 5, 5, etc., extending all the way around the periphery. and clamping the cover to the casing with anairtight seal 6 in between the top and the clamping edge/and composed of material transparent to waves such as Bakelite, glass or ceramic. Mounted on the base 'I of the casing is a supporting bracket 8 containing the spark-oscillating device 9 of the general type described in my copending application Serial No. 362,434, filed October 23, 1940, but differing in certain respects which will be described later. and II are mounted in the base 'I of the chamber I and provide a support respectively for the conductors I2 and I3 in series with each of which are resistors I4 and I5 and the spark gaps I 6 and I'I, respectively. The spark gaps I6 and I1 are opposed to the terminals I8 and I9, respectively, which, in turn, connect to the metallic cones and 2| tapering to. center points 22 f and 23 which are preferably of some hard metal such as tungsten. The cones 20 and 2| are supported by mica insulating plates 24 and 25, re-

spectively, which are mounted at the ends of the element 26 which is cylindrical in its outer shape with the interior hollowed out to the shape of cones so that the inner surfaces 21 and 28 are respectively spaced away from the sides of the cones 29 and 2i.

The element 26 at its end has iiat sections 29 and 30 against which the mica insulating sheets 24 and 25 are held fast. In back of the casing 2 in a second chamber 3I, which need not be air tight, is mounted an air core transformer 32 whose secondary 33 supplies power to the spark tank circuit and the primary 34 of which is connected through the concentric cable 35 to the power supply source which is more completely described in Fig. 6.

In Fig. 6 the air core transformer 32 with the output secondary 33 and the input primary 34 may be operated and controlled through a circuit in which a thyratron tube 41 initiates the discharge through one of the condensers C1, C2 or C3 through` the proper connection of the switch 44. The condensers C1, C2 and Cs are charged by the direct current high potential source indicated at 46 through one of the resistances R1 to R5 depending upon the position of the switch 45. The condensers are discharged by means of the thyratron tube 41 the grid of which is biased by the battery 48 in series with a triggering oscillating source 49 which may be sinusoidal peaked or saw-toothed in shape and Two high-tension insulators Ill cuit is substantially snorted, but the damping of the discharge is controlled by the adjustable resistance 43 to provide one major oscillation with only minor subsequent ones insufiicient to cause a breakdown of the oscillator spark circuit.

In the operation of the system shown in Fig. 1,

the tank circuit is charged across from the spark point I6 to the spark point I1 which, in turn, breaks down with the breakdown of th'e sparking points 22 and 23, thus causing an oscillation of electrical energy in the cones '20 and 2l and a radiation in the direction of the horn 50.

In the modification shown in Figs. 2, 3 and 4 an arrangement showing substantially half of the member 9 is illustrated. In this case the central conical element l is supported by the conical shell 52 by means of the mica disc 53 through the screws 54 holding the cone 5I to the mica and screws 55 holding the mica disc to the external cone 52. A uniform space 56 is provided between the elements 5| and 52. At the apex of the cone 5I there is attached a tungsten or other sparking point 51 which is opposed by the point 58 adjustably positioned by means of the screws 59 on which the spark 58 is mounted. The screw 59 threads through the cylindrical end 60 of the element 52 and permits an adjustment by means of the screw 59 of the spark gap along the center axis of the cone. so that the adjustment of the gap may be properly viewed. Mounted in the cone element 5I may be the antenna 62 which may be of such a dimension as to provide the desired resonance in tuning of the system.

Having now described my invention, I claim:

l. A spark transmitting system for ultra-high radio frequency comprising, in combination, a metallic casing having one side transparent to electromagnetic waves, an ultra high frequency radiation and tank circuit coupled together and positioned within said casing comprising two opposed conducting conical members with apices aligned along a common central axis of revolution of the cones lproviding the sparking points, means providing a continuous conductive surface closely spaced to the surfaces of said conical members but further apart therefrom than the sparking points, insulating means supporting and positioning said conical members with respect to the means providing said continuous conductive surface, and means mounted on a side of said metallic casing supporting said means providing a continuous conductive surface.

2. In combination in an ultra high frequency spark transmitting system, a metallic horn having a metallic casing attached to the throat of the horn with a partition, transparent to electro-magnetic waves between the metallic casing and the horn, an ultra frequency radiation and tank circuit coupled together and positioned within said metalliccasing comprising two opposed conical conducting members with apices aligned along a common central axis of revolution of the conical-members, the tips of which provides sparking points from one to the other, means providing a, continuous conducting surface closely-spacedvto th'e surfaces of the conical members, but further apart therefrom than the sparking points, insulating means supporting and positioning said conical members with respect to the means providing said continuous conductive surface, and means mounted on a side of said metallic casing supporting the said means providing a continuous conductive surface.

3. In combination in an ultra high frequency spark transmitting system, a metallic horn having a metallic casing attached to the throat of the A window 6I is provided horn with a partition transparent to electromagnetic waves between the metallic casing and the horn, an ultra high frequency radiation and tank circuit coupled together and positioned within said metallic casing, said circuit having sparking points aligned along an axis substanftially perpendicular to the axis of the horn at its throat, means supporting said radiation and tank circuit from the wall of the casing opposite th'e transparent partition, and electrical conducting means passing through said last partition and providing conducting members to energize said circuit.

4. In combination in an ultra frequency spark transmitting system, a metallic horn having a metallic casing attached to the throat of the horn with a partition transparent to electro-magnetic waves between the metallic casing and the horn, an ultra high frequency radiation and tank circuit coupled together and positioned within said metallic casing, said circuit having sparking points aligned along an axis substantially perpendicular to the axis of the horn at its throat, means supporting said radiation and tank 'circuit from the wall of the casing opposite the transparent partition and electrical conducting means passing through said last partition and providing conducting members to energize said circuit, said -conductingmeans having auxiliary sparking electrode connected in series with parts of said circuit.

HUGO BENIOFF.

REFERENCES CITED The Ifollowing references are of record in the file of this patent:v

UNITED STATES PATENTS Number Name Date 2,240,941 Ohl May 6, 1941 897,279- Fessenden Sept. l, 1908 1,117,681 Loeilier Nov. 17, 1914 

